Microbial Fuel Cell May Power Medical Implants One Day

The fuel cell recruits necessary bacteria to create a biofilm that utilizes natural organic compounds as fuel to generate power.

Through outstanding research at Carnegie Mellon University (CMU),
McGowan Institute for Regenerative Medicine affiliated faculty member Philip LeDuc, PhD (pictured), CMU associate professor of mechanical engineering with courtesy appointments in Biomedical Engineering, Biological Sciences, and Computational Biology departments, and a team of scientists developed renewable energy using bacteria and microtechnology. The world’s smallest microbial fuel cell could be used to power underwater remote sensors or even medical implants.

As reported, the new device, the size of a single strand of human hair (total volume of just 0.3 microliters), generates energy from the metabolism of bacteria on thin gold plates in micro-manufactured channels. The fuel cell recruits necessary bacteria to create a biofilm that utilizes natural organic compounds as fuel to generate power.

Future versions of this tiny bacteria-powered fuel cell could replace batteries in microelectronic devices. While batteries are used to do that today, fuel cells are able to store more energy in the same space.

"Our biology-powered fuel cell could be less costly to make and more easily deployed in remote areas than conventional batteries that require invasive maintenance," said Dr. LeDuc, a co-author of the study.

For now, however, the microbial fuel cells produce only very tiny amounts of electricity — up to 127 amps per cubic meter, about 7,000 times less than a AA battery, said Kelvin Gregory, co-author and an assistant professor of civil and environmental engineering at CMU. At this level, a single microfluidic microbial cell could potentially power itself as a remote sensor, but for larger applications, many cells would need to be stacked together to increase the power output. Luckily, multiplexing is a common feature of microfluidics, said Dr. LeDuc. “It’s like computer chips — you can put a ton of these things in parallel.”